The complete Salvia Guide

Salvia Embers Wish 3

Common name: Sage

Latin name: Salvia

Height: from 20 to 200cm

Aspect: Sun or partial shade

Soil Type: Well Drained/ No sitting water

Flowering Period: Spring to Autumn

Hardiness: Frost hardy to -7

RHS Hardiness Rating: H2 to H5

Types of Salvia

Salvias have gained immense popularity due to their extended flowering period, lasting from May to September, sometimes even into October. The optimal time for planting salvias is late April to early June, or as soon as the risk of late spring frosts has diminished. This allows the plants ample time to establish and develop strong roots before winter. If purchased late in the season, it is advisable to keep them frost-free and plant them in the following spring.

The salvia genus comprises over 900 species and belongs to the Lamiaceae or mint family, characterized by lip-shaped flowers. Traditionally known as sage, it has been utilized for its beneficial and medicinal properties.

Various flowering varieties from Mexico, Central and South America, and the Southern states of the USA have gained popularity in European countries like the UK. This is attributed to their prolonged flowering season and the diverse range of flowers and leaf shapes they offer.

Salvias are effective pollinators, attracting bees, bumblebees, moths, and hummingbirds, especially in tropical climates.

Experts and growers categorize salvias into three groups based mainly on their winter hardiness:

  1. Hardy Herbaceous (up to -22°C)
  2. Hardy Bushy Salvias (up to -8°C to -12°C)
  3. Semi-Winter Hardy and Frost-Sensitive Salvias (0°C to -8°C)

How to grow salvias

Position

For optimal growth and blooming, Salvias thrive in a light, free-draining soil under full sun. In colder regions, it’s advisable to locate them in a sheltered area, like beside a sunny, south-facing wall.

Soil Type

While Salvias don’t necessitate rich humus soil, they do benefit from regular feeding. Applying a general feed in late spring and a liquid feed throughout the summer, particularly high in potash, enhances flowering. Planting Salvias in tubs or pots is a great option for vibrant patio displays, and John Innes No. 3 compost is suitable. Salvias, being drought-tolerant, are an excellent choice for areas with low rainfall.

Time of year to plant

The best time to plant Salvias is in spring and early summer, allowing them to establish a robust root system before winter. Semi-hardy species should be kept in a warm, protected place from northeastern winds. Most Salvias thrive in full sun, although there are exceptions. Larger-leaved varieties can tolerate more shade.

Pruning

Perform a significant pruning in early spring to encourage bushier growth and more blooms. Repeat a second decent pruning in mid-July for exuberant autumn blooms.

Pruning

Perform a hard pruning in late spring when new growth appears, cutting all the dead foliage from the winter just above the emerging shoots. Within a few weeks, the plant will burst into color, with flowers starting to appear from late April onwards. As the plant becomes leggy in mid to late summer, prune again to stimulate new growth of foliage and flowers well into the autumn. These varieties are easy to grow, making them a great introduction to the Salvia collecting experience.

Avoid complete pruning in the winter. In early April, you can cut the plants down to one-third once they start shooting.

Common Pests

Salvias typically attract two types of pests: greenfly and capsid bugs. To control greenfly, use soapy water sprayed over the leaves. For capsid bugs, the use of provado is crucial, as it helps prevent distorted growth.

Winter Care

  1. Hardy Herbaceous (up to -22°C)

Fully hardy salvias, such as Salvia nemorosa, S. verticillata, S. pratensis, and S. sylvestris, can withstand winter temperatures as low as -22°C. These plants can be left outside, and they will survive the winter.

2. Hardy Bushy Salvia (up to -8 °C to -12 °C)

This category includes popular varieties like microphylla, greggii, and x jamensis, known for blooming in full sun from May to November. They typically survive most reasonable winters in England. Adding some leaf mould around the base during harsh winters provides extra protection. A slight pruning in late summer can stimulate further flowering until the frosts. Hybrids like involucrata, guaranitica, and uliginosa are also hardy in certain areas of the country.

3. Semi-Winter Hardy and Frost-Sensitive Salvia (0 °C to -8 °C)

This group comprises many Latin American and Californian varieties. They require protection during winter, either in greenhouses or cold frames, to shield them from frost. Taking cuttings as a precautionary measure and keeping them frost-free is advisable. Several varieties from the Love and Wishes range are not hardy and will need protection.

Taking Cuttings

Cuttings should be taken in August or September, providing numerous new plants for your garden or to share with others.

When selecting a cutting, ensure the stem has at least three nodes. While two nodes are sufficient, opting for a stem with three nodes increases the likelihood of the cutting growing into a larger, more prolific plant.

Using secateurs, cut the stem just below the bottom node. These nodes contain a specific plant growth hormone, auxin, which stimulates both leaf and root growth.

After obtaining the cutting, dip it into a rooting hormone. This encourages faster development of new roots in the coming days.

Place the cuttings in well-draining soil, ensuring they receive full sunlight, preferably in a south-facing location. Water the cuttings and cover the pot with a clear plastic bag to protect them from strong winds.